The present invention relates generally to the computer-aided design and manufacture of custom tile mosaics of ceramic or other materials. Much of the description of the process and apparatus refers specifically to the production of ceramic tile mosaics, the preferred embodiment, but the same basic procedures apply in producing mosaics from other materials.
Current commercial ceramic tile-forming methods include ram-pressing, dry-pressing, and extrusion. All produce in a single run many tiles of the same size and shape, and they are all usually glazed with a single color, in a typical mechanical mass production fashion. When conventional tiles are installed, some must be cut to fit, which requires time and produces waste.
In the tile industry of the 1980's "mosaic tile" refers to small tiles, usually matted (glued in square arrays to perforated paper, plastic, or fabric backing for easy installation), and usually all the same shape and color. Some multi-color and multi-shape matted tile patterns are available as stock items. Also available as stock items, intended to meet the increasing demand for decorative tiles, are larger non-matted square tiles stamped and/or printed with mosaic patterns or other designs.
There is a growing demand for finely detailed architectural ornament, but there has been no way to design and produce affordable custom ceramic mosaics and complex geometric tilings. Making mosaics by hand and making tiles of complex shape by hand are time-consuming and require special skills.
In 1988 and 1989, at least two companies (Colorco, in Merrimack, N.H. and Digitile in Seattle, Wash.) began using microcomputers to offer a partial solution to this problem. In their schemes, pixels in the scanned-in image on the computer's display are resampled to a single size that represents the size of the tiles that will comprise the mosaic. Then the mosaic design is divided by software into installable-sized sections (1 foot by 1 or 2 feet, for example). These sections are manufactured from already-fired and glazed square or round tiles, either by hand on computer-printed patterns or by use of a pick-and-place robot that picks up tiles of different colors and places them appropriately on glue-covered mats. The disadvantage of the mosaics produced by these schemes is that edges and lines in the design that are not horizontal or vertical have stair-stepped edges, similar to many other displays and outputs of images generated by computers. The tiles in these mosaics are all the same size, and are all in even rectilinear rows and columns. Reducing pixel size, i.e. tile size, improves the appearance of these mosaics, but the stair-stepping problem can never be eliminated with this approach.
The state of the art of advanced methods of tile mosaic creation and in other fields brought together through the present invention is exemplified in the above-described schemes and in the following:
______________________________________ U.S. Patent Documents ______________________________________ 4,868,003 Temple et al 427/50, 118/715 4,698,192 Kuze et al 264/101 ______________________________________